Why georeferencing matters: Introducing a practical protocol to prepare species occurrence records for spatial...

Area of Science:

• Ecology
• Biogeography
• Computational Biology

Background:

• Species Distribution Models (SDMs) are essential tools for understanding species' environmental ranges and predicting shifts due to climate change.
• The accuracy of SDMs is heavily dependent on the quality of input occurrence data, particularly precise geographic coordinates.
• Museum records often lack accurate georeferencing, necessitating verification for reliable SDM development.

Purpose of the Study:

• To introduce and evaluate a standardized manual georeferencing protocol (Spatial Analysis Georeferencing Accuracy - SAGA) for museum records.
• To assess the impact of georeferencing accuracy on the performance of Species Distribution Models (SDMs).
• To improve the geographic precision of occurrence data for enhanced SDM predictions, especially for future climate scenarios.

Main Methods:

• Developed and applied the Spatial Analysis Georeferencing Accuracy (SAGA) protocol for manual georeferencing of museum records to a ≤1-km resolution.
• Generated and compared three sets of SDMs using MAXENT with occurrence data subjected to different georeferencing levels: raw, pre-georeferenced, and SAGA-protocol georeferenced.
• Utilized the high-elevation plant *Saxifraga austromontana* as a case study to evaluate the protocol's effectiveness.

Main Results:

• Species Distribution Models (SDMs) built with SAGA-protocol georeferenced data significantly outperformed models using raw or previously georeferenced data.
• Georeferencing accuracy demonstrably influenced model predictions of suitable habitat for *Saxifraga austromontana*.
• Discrepancies among model predictions were amplified when forecasting future species distributions under climate change scenarios.

Conclusions:

• Accurate georeferencing of museum records is critical for producing reliable SDMs and accurate forecasts of species range shifts.
• The SAGA protocol offers a practical, standardized method to enhance geographic accuracy of museum data for ecological modeling.
• Adoption of standardized georeferencing protocols by researchers and curators is essential for improving the utility of museum collections in spatial analyses and conservation efforts.